A new BLSA study of Prostate Growth and Disease was begun in February 1993 to examine anatomic and physiologic correlates of normal prostate growth and the development and progression of benign prostatic hyperplasia and prostate cancer. In the past year, four studies have been completed. A BLSA study of clinical markers of poor prognosis from prostate cancer (PCa) found that prostate-specific antigen (PSA) level and PSA velocity (rate of change) prior to diagnosis were not strong predictors of progression to metastasis or death from PCa. The second BLSA study showed that the epithelial composition of the prostates of men with benign prostatic hyperplasia (BPH) was positively correlated with PSA level and PSA velocity. Thus, PSA could be useful as an inexpensive method of targeting drug treatments at either the epithelial or stromal components of BPH. The third study developed formulas utilizing PSA level, histologic grade and clinical stage to predict whether the cancer had spread outside the prostatic capsule, into the seminal vesicles, or lymph nodes in 703 patients from Johns Hopkins Hospital. Clinicians will use the formulas to guide treatment decisions. The fourth study examined clinical markers of local or distant recurrence of prostate cancer in men who have undergone radical prostatectomy. PSA level, PSA velocity, Gleason score, and pathologic stage were assessed among a clinical series from Johns Hopkins Hospital of 51 radical prostatectomy patients who had either a local or distant recurrence of PCa. PSA velocity was the strongest predictor of type of recurrence, along with Gleason Score and pathologic stage. These findings suggest that PSA velocity is an important clinical tool for guiding treatment of recurrences of prostate cancer after radical prostatectomy.